This invention relates to a sun sensing arrangement for a motor vehicle including a sensor for detecting incident sunlight and the motor vehicle having an engine hood which has a top-side air inlet grid area. This invention also relates to a method of arranging a sun sensor in a motor vehicle.
It is generally known to arrange one or several sun sensors in a motor vehicle which sense sunlight radiated onto the motor vehicle with respect to its intensity and optionally also with respect to its radiation direction and which supply the information obtained from this or these sensor(s) as an analog or digital signal to an interior-temperature control device so that the control device will be capable of controlling the temperature of the interior of the motor vehicle as a function of the sun radiation.
It is understood that the sun sensor, which usually contains one or several light-sensitive diodes or resistance elements, must be arranged on a surface of the vehicle which is accessible to the incident sunlight, that is, is exposed to the light radiation in the upward direction. U.S. Pat. No. 4,917,293 shows a radiation sensor which is exposed in the upward direction. Specifically, it is known in this respect, for example, from German Published Patent Document DE 38 21 743 A1 and U.S. Pat. No. 5,186,682, to mount the sun sensor or sensors on the dashboard in the vehicle interior where they do not interfere with the styling of the shell of the vehicle body and are protected from environmental influences. However, in the case of this mounting site, the effective sensing angle range is generally limited by shading as a result of light-impermeable A-column areas and of the forward roof area. In addition, the light reaching the sun sensor must pass through one of the vehicle windows. Depending on the type of window pane and any tinting applied thereto, different reflection and absorption effects may occur which influence the measuring result of the sun sensor.
An object of the present invention is to provide a motor vehicle with a sun sensor which has a relatively large sensing angle range, is exposed to only relatively low external interferences, does not noticeably impair the vehicle styling, and permits a sensing of the sunlight which is not influenced by the vehicle windows or vehicle body columns.
This and other objects have been achieved according to the present invention by providing a sun sensing arrangement for a motor vehicle, comprising: an engine hood having a top-side air inlet grid area; and at least one sun sensor for sensing incident sunlight arranged within the air inlet grid area of the engine hood.
This and other objects have also been achieved according to the present invention by providing a method of arranging a sun sensor in a motor vehicle including an engine hood having a top-side air inlet grid area, the method comprising the step of arranging at least one sun sensor for sensing incident sunlight within the air inlet grid area of the engine hood.
According to the present invention, the sun sensor is arranged inside the air inlet grid area of the engine hood. This permits an almost hemispherical sensing angle range with only slight shading. The sensor signal remains independent of the types of glass and/or tinting in each case used for the different vehicle windows and therefore always is a reliable measurement for the actual sun radiation onto the vehicle. The installation of the sun sensor in the air inlet grid of the vehicle hood can take place in a stylistically inconspicuous manner, and the visual appearance of the roof of the vehicle remains unchanged. In addition, in the case of this mounting site, there is no danger of a shading of the sensor as a result of accessories, such as ski racks, bicycle racks, etc. mounted on the outside of the vehicle.
These and other objects, features and advantages of the present invention will become more readily apparent from the following detailed description when taken in conjunction with the accompanying drawings.